In the past, the number of different filtering systems have been embodied in liquid-vacuum cleaning equipment such as may be used for cleaning carpets and upholstery. Such filtering systems are the subject of U.S. Pat. No. 4,696,075 issued Sep. 29, 1987 to Dale L. Grave of Plymouth, Minn., and an application for U.S. patent Ser. No. 7/556,175, filed Jul. 23, 1990, invented by Robert M. Barry, inventor of the present invention disclosed therein and assigned to a common assignee, CFR Corporation of Roseville, Minn. The prior inventions identified above relate to filter systems which rely on back washing of the filter element when the pumping system is in a bypass mode of operation and ultimately requires replacement of a filter cartridge when back wash cleaning is no longer effective.
My present system permits bypass recirculation of liquid without circulation through the filtering assembly and also provides a relatively simple yet versatile filtering system which eliminates the need for frequent filter replacement by providing reusable filter elements and an extremely easy to change simplified filter assembly design.